If a number in the trillions doesn't make you pause, realize that it means roughly 64,109 years of playtime. Years. 640 centuries. 6,400 decades. More than 800 times the average human lifespan.
To knock a little more perspective into you, Bungie notes that 64,000 years ago neanderthal walked the earth and modern man had yet to set foot in Asia.
It makes you want to get offline and spend a day at the park or something, doesn't it?
I don't play Halo, but I play a million online flash games and otherwise spend a ridiculous amount of time doing absolutely nothing but trying to explore the vast corners of the Web. So even though my contribution to that astounding two trillion second count rounds up to roughly zero, I'm still re-thinking my screen time. How about you?